visad
Class DateTime

java.lang.Object
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  +--visad.ThingImpl
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        +--visad.DataImpl
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              +--visad.Scalar
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                    +--visad.Real
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                          +--visad.DateTime
public final class DateTime
extends Real

DateTime is a class of objects for holding date and time information. DateTime objects are immutable.

Internally, the object uses seconds since the epoch (1970-01-01 00:00:00Z) as the temporal reference.

See Also:
java.lang.System#currentTimeMillis(), Serialized Form

Inner classes inherited from class visad.DataImpl
DataImpl.Syncher
 
Inner classes inherited from class visad.ThingImpl
ThingImpl.RemotePair
 
Field Summary
static String DEFAULT_TIME_FORMAT
          Default Time Format Pattern (yyyy-MM-dd HH:mm:ss)
static TimeZone DEFAULT_TIMEZONE
          Default Time Zone (GMT)
 
Fields inherited from class visad.DataImpl
Type
 
Constructor Summary
DateTime()
          Construct a DateTime object and initialize it to the current date/time.
DateTime(Date date)
          Construct a DateTime object and initialize it with a Java date.
DateTime(double seconds)
          Construct a DateTime object and initialize it with the seconds since January 1, 1970 00:00:00Z.
DateTime(double timeValue, Unit timeUnits)
          Construct a DateTime object from a number of value and a Unit
DateTime(int year, int day, double seconds)
          Construct a DateTime object initialized with a year, day of the year, and seconds in the day.
DateTime(Real real)
          Construct a DateTime object and initialize it using a VisAD Real.
 
Method Summary
 int compareTo(Object oo)
          Implement Comparable interface
static DateTime createDateTime(String dateString)
          Create a DateTime object from a string specification
static DateTime createDateTime(String dateString, String format)
          Create a DateTime object from a string specification using the supplied pattern and default timezone.
static DateTime createDateTime(String dateString, String format, TimeZone timezone)
          Create a DateTime object from a string specification using the supplied pattern and timezone.
 String dateString()
          Return a string representing the "date" portion of this DateTime
 String formattedString(String pattern, TimeZone timezone)
          Return a string representation of this DateTime from a user specified format.
static Real fromYearDaySeconds(int year, int day, double seconds)
          Return a Real object whose value is the seconds since the Epoch initialized with a year, day of the year, and seconds in the day.
static String getFormatPattern()
          Return the format pattern used in the output of the toString() method.
static TimeZone getFormatTimeZone()
          Return the TimeZone used in the output of the toString() method.
 Real getReal()
          Get a Real representing the number of seconds since * the epoch.
static void main(String[] args)
          run 'java visad.DateTime' to test the DateTime class
static Gridded1DDoubleSet makeTimeSet(DateTime[] times)
          Create a Gridded1DDoubleSet from an array of DateTimes
static Gridded1DDoubleSet makeTimeSet(double[] times)
          Create a Gridded1DDoubleSet from an array of doubles of seconds since the epoch.
static void resetFormat()
          Reset the format of the output of the toString() method to the default - yyyy-MM-dd HH:mm:ssZ (ex: 1999-05-04 15:27:08Z) and the TimeZone to UTC.
static void setFormatPattern(String pattern)
          Set the format of the output of the toString() method.
static void setFormatTimeZone(TimeZone tz)
          Set the TimeZone of the output of the toString() method.
static DateTime[] timeSetToArray(Gridded1DSet timeSet)
          Create an array of DateTimes from a Gridded1DSet of times.
 String timeString()
          Return a string representing the "time" portion of this DateTime
 String toString()
          Return a string representation of this DateTime.
 String toValueString()
          Gets a string that represents just the value portion of this DateTime -- but with full semantics.
 
Methods inherited from class visad.Real
__eq__, __eq__, __float__, __ge__, __ge__, __gt__, __gt__, __int__, __le__, __le__, __long__, __lt__, __lt__, __ne__, __ne__, adjustSamplingError, binary, cloneButUnit, cloneButValue, computeRanges, equals, getError, getUnit, getValue, getValue, hashCode, isMissing, longString, unary
 
Methods inherited from class visad.Scalar
addReference, clone, removeReference
 
Methods inherited from class visad.DataImpl
__add__, __add__, __div__, __div__, __mod__, __mod__, __mul__, __mul__, __neg__, __pow__, __pow__, __radd__, __rdiv__, __rmod__, __rmul__, __rpow__, __rsub__, __sub__, __sub__, abs, abs, acos, acos, acosDegrees, acosDegrees, add, add, asin, asin, asinDegrees, asinDegrees, atan, atan, atan2, atan2, atan2Degrees, atan2Degrees, atanDegrees, atanDegrees, binary, ceil, ceil, changeMathType, computeRanges, computeRanges, computeReferenceRanges, cos, cos, cosDegrees, cosDegrees, dataClone, divide, divide, exp, exp, floor, floor, getType, invertOp, local, log, log, longString, max, max, min, min, multiply, multiply, negate, negate, notifyReferences, pow, pow, remainder, remainder, rint, rint, round, round, setParent, sin, sin, sinDegrees, sinDegrees, sqrt, sqrt, subtract, subtract, tan, tan, tanDegrees, tanDegrees, unary
 
Methods inherited from class visad.ThingImpl
adaptedAddReference, adaptedRemoveReference
 
Methods inherited from class java.lang.Object
, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

DEFAULT_TIME_FORMAT

public static final String DEFAULT_TIME_FORMAT
Default Time Format Pattern (yyyy-MM-dd HH:mm:ss)

DEFAULT_TIMEZONE

public static final TimeZone DEFAULT_TIMEZONE
Default Time Zone (GMT)
Constructor Detail

DateTime

public DateTime(Real real)
         throws VisADException
Construct a DateTime object and initialize it using a VisAD Real. Unless the units of the Real specify otherwise, the Real's value is assumed to be seconds since the Epoch (i.e. 1970-01-01 00:00:00Z).
Parameters:
real - Real value in a temporal unit.
Throws:
VisADException - unit conversion problem

DateTime

public DateTime(double seconds)
         throws VisADException
Construct a DateTime object and initialize it with the seconds since January 1, 1970 00:00:00Z.
Parameters:
seconds - number of seconds since 1970-01-01 00:00:00Z.
Throws:
VisADException - unit conversion problem

DateTime

public DateTime(double timeValue,
                Unit timeUnits)
         throws VisADException
Construct a DateTime object from a number of value and a Unit
Parameters:
timeValue - value of time in timeUnits
timeUnits - units of value

DateTime

public DateTime(Date date)
         throws VisADException
Construct a DateTime object and initialize it with a Java date.
Parameters:
date - date object
Throws:
VisADException - unit conversion problem

DateTime

public DateTime()
         throws VisADException
Construct a DateTime object and initialize it to the current date/time.
Throws:
VisADException - unit conversion problem

DateTime

public DateTime(int year,
                int day,
                double seconds)
         throws VisADException
Construct a DateTime object initialized with a year, day of the year, and seconds in the day.
Parameters:
year - year - use negative year to indicated BC
day - day of the year
seconds - seconds in the day
Throws:
VisADException - invalid day or seconds. Days must be greater than zero and seconds must be greater than zero and less than or equal to the seconds in a day.
Method Detail

fromYearDaySeconds

public static Real fromYearDaySeconds(int year,
                                      int day,
                                      double seconds)
                               throws VisADException
Return a Real object whose value is the seconds since the Epoch initialized with a year, day of the year, and seconds in the day.
Parameters:
year - year - use negative year to indicated BC
day - day of the year
seconds - seconds in the day
Throws:
VisADException - invalid day or seconds. Days must be greater than zero and seconds must be greater than zero and less than or equal to the seconds in a day.

getReal

public Real getReal()
Get a Real representing the number of seconds since * the epoch.
Returns:
this object

toString

public String toString()
Return a string representation of this DateTime. Unless the setFormatPattern() and/or setTimeZone() methods were used, the default it the ISO 8601 complete date plus hours, minutes and seconds and a time zone of UTC. See http://www.w3.org/TR/NOTE-datetime
Returns:
String representing the date/time. Default is yyyy-MM-dd HH:mm:ssZ (ex: 1999-05-04 15:27:08Z)
Overrides:
toString in class Real
See Also:
setFormatPattern(java.lang.String), setFormatTimeZone(java.util.TimeZone)

toValueString

public String toValueString()
Gets a string that represents just the value portion of this DateTime -- but with full semantics.
Returns:
String representing the date/time in the form yyyy-MM-dd HH:mm:ssZ (ex: 1999-05-04 15:27:08Z)
Overrides:
toValueString in class Real

formattedString

public String formattedString(String pattern,
                              TimeZone timezone)
Return a string representation of this DateTime from a user specified format. The pattern uses the time format syntax of java.text.SimpleDateFormat and the time zone is any of the valid java.util.TimeZone values.
Parameters:
pattern - time format string
timezone - time zone to use
Returns:
String representing the date/time in the form specified by the pattern.
See Also:
SimpleDateFormat, TimeZone

dateString

public String dateString()
Return a string representing the "date" portion of this DateTime
Returns:
String representing the date (UTC) in the form yyyy-MM-dd (ex: 1999-05-04).

timeString

public String timeString()
Return a string representing the "time" portion of this DateTime
Returns:
String representing the time (UTC) in the form HH:mm:ssZ (ex: 15:27:08Z)

setFormatPattern

public static void setFormatPattern(String pattern)
Set the format of the output of the toString() method. All DateTime objects created in the JVM once this is set will use the new format so be very careful in your use of this method. The pattern uses the time format syntax of java.text.SimpleDateFormat.
Parameters:
pattern - time format string
See Also:
If you want to use a time zone other than the default,, setFormatTimeZone(java.util.TimeZone)

getFormatPattern

public static String getFormatPattern()
Return the format pattern used in the output of the toString() method. The pattern uses the time format syntax of java.text.SimpleDateFormat.
Returns:
time format pattern
See Also:
SimpleDateFormat

setFormatTimeZone

public static void setFormatTimeZone(TimeZone tz)
Set the TimeZone of the output of the toString() method. All DateTime objects created in the JVM once this is set will use the new TimeZone so be very careful in your use of this method. The time zone is any of the valid java.util.TimeZone values.
Parameters:
tz - time zone
See Also:
TimeZone

getFormatTimeZone

public static TimeZone getFormatTimeZone()
Return the TimeZone used in the output of the toString() method.
Returns:
time zone

resetFormat

public static void resetFormat()
Reset the format of the output of the toString() method to the default - yyyy-MM-dd HH:mm:ssZ (ex: 1999-05-04 15:27:08Z) and the TimeZone to UTC.

createDateTime

public static DateTime createDateTime(String dateString)
                               throws VisADException
Create a DateTime object from a string specification
Parameters:
dateString - date string specification in format pattern defined for DateTime in this JVM
Throws:
VisADException - formatting problem
See Also:
setFormatPattern(java.lang.String)

createDateTime

public static DateTime createDateTime(String dateString,
                                      String format)
                               throws VisADException
Create a DateTime object from a string specification using the supplied pattern and default timezone.
Parameters:
dateString - date string specification
format - string
Throws:
VisADException - formatting problem

createDateTime

public static DateTime createDateTime(String dateString,
                                      String format,
                                      TimeZone timezone)
                               throws VisADException
Create a DateTime object from a string specification using the supplied pattern and timezone.
Parameters:
dateString - date string specification
formatPattern - format string
timezone - TimeZone to use
Throws:
VisADException - formatting problem

compareTo

public int compareTo(Object oo)
Implement Comparable interface
Parameters:
oo - Object for comparison - should be DateTime
Overrides:
compareTo in class Real

makeTimeSet

public static Gridded1DDoubleSet makeTimeSet(DateTime[] times)
                                      throws VisADException
Create a Gridded1DDoubleSet from an array of DateTimes
Parameters:
times - array of DateTimes. Array cannot be null or only have one entry.
Returns:
Gridded1DDouble set representing the array
Throws:
VisADException - couldn't create the GriddedDoubleSet

makeTimeSet

public static Gridded1DDoubleSet makeTimeSet(double[] times)
                                      throws VisADException
Create a Gridded1DDoubleSet from an array of doubles of seconds since the epoch.
Parameters:
times - array of times in seconds since the epoch. Array cannot be null or only have one entry.
Returns:
set representing the array as a Gridded1DDoubleSet
Throws:
VisADException - couldn't create the GriddedDoubleSet

timeSetToArray

public static DateTime[] timeSetToArray(Gridded1DSet timeSet)
                                 throws VisADException
Create an array of DateTimes from a Gridded1DSet of times.
Parameters:
timeSet - Gridded1DSet of times
Throws:
VisADException - invalid time set or couldn't create DateTimes

main

public static void main(String[] args)
                 throws VisADException
run 'java visad.DateTime' to test the DateTime class